The Habitable PlanetHabitable Planet home page

Interactive Labs

Ecology Lab

Tools of the Simulator

Simulator Controls

Reset Button
Returns to Day 0.
Stop Button
Stops the progression of the simulator at the moment it is clicked.
Step
Simulates the progression of population as determined by the parameters for one day.
Run
Simulates the progression of population as determined by the parameters for one hundred days, or, if you have already run the simulator using "Step," "Run" continues the progression to day 100.
Tableau
Pull–down menu in the lower right–hand corner. There are two settings: Plants and Many. The most visible difference among these tableaus are automatic changes in the food web (See Food Web), which result in automatic changes in the interactive illustration (see Interactive Illustration).

Simulator Parameters: Food Web

This visual representation of the food web shows the organisms in the web as well as the flow of energy within the web. There are four main categories in the food web: Plants (Producers), Herbivores, Omnivores, and Top Predator.

Plants
These species represent the available producers for your simulated ecosystem. Note that if plants alone are present in the ecosystem, there will be no energy flow (connecting lines) in the food web. The default setting has Plants A and B present in the Plants and Many tableaus. However, you may alter these choices and select which species you want to be present in your ecosystem. Using your mouse, left click a Plant species box and a window will appear showing the name of the species and Exit listed beneath. If you want to include the species in the simulation, highlight and click the name of the species. It will then be added to the species already present and a check mark will appear next to its name. If you do not want to include it, highlight and click on Exit. If you want to remove a species, simply left–click the species box and then highlight and click the species name to remove the check mark.
Herbivores
These species represent the available plant-eaters for your simulated ecosystem. The default setting has Herbivore A present in the Many tableau. You may alter this and select which species you want to be present in your ecosystem. Using your mouse, left click an Herbivore species box and a window will appear showing the name of the species, a list of possible actions, and Exit. Choose the species you want to be food for your Herbivore by highlighting and clicking that species. For example, left clicking Herbivore A will give you the following:
You may choose to have your Herbivore eat as many plant species as are present in the simulator for the tableau you have selected. If you wish to make NO changes, simply move your mouse over Exit and click.
Omnivores
These species represent the available plant and meat eaters for your simulated ecosystem. The default setting has both Omnivores A and B present in the Many tableau. However, ,you may alter this choice and select which species you want to be present in your ecosystem. Using your mouse, left click an Omnivore species box and a window will appear showing the name of the species, a list of possible actions, and Exit. Select the plant species and the herbivores on which your chosen Omnivore will feed by highlighting and clicking that species. For example, clicking Omnivore A will give you the following:
If you wish to make NO changes, simply move your mouse over Exit and click. You may choose to have your Omnivore eat as many species as are present in the simulator for the tableau you have selected.
Top Predator
This species represents the available meat eaters for your simulated ecosystem. The default setting allows the top predator to appear only in the Many tableau. Using your mouse, left click the Top Predator species box and a window will appear showing the name of the species, a list of possible actions, and Exit. Select the species on which your predator will feed. Clicking the Top Predator species box will give you the following:
If you wish to make NO changes, simply move your mouse over Exit and click. You may choose to have your predator eat as many species as are present in the simulator for the tableau you have selected.
Connecting Lines
These lines represent the flow of energy in the ecosystem. The connection between two species means that one of the species (generally the one higher in the web) will feed on the other, propagating the flow of energy. One species may be connected to any number of others, including none.
Preset button
Restores default setting in each tableau.
All on button
Includes all species carrying out all possible actions.
All off button
Removes all species from the ecosystem.

Population by Species Graph

The graph shows the progression of the food web and the species present in the ecosystem as a function of time and within your chosen parameters. The legend box may be moved by dragging it with your mouse. The y-axis is the population and the x-axis is the day.

Depending on which species you have chosen to take part in the ecosystem, anywhere from one to nine lines may appear on the graph. Each line will be color coded to match the species box. As the simulator progresses, using your mouse, you may rollover any line in order to see the data for that species on that day.

Interactive Illustration

Each species is color coded to match the species box as well as the colored line on the graph. The number of pictures of a species in the interactive illustration is not directly correlated to the population number for that species, but is representative of the density of that species relative to the others and the general species size (the average size of the organism).

Watching the illustration as the simulator runs, you may visualize how the food web operates and species spread, given your set parameters. This simulator mimics the food web within a diverse ecosystem and gives a probable, if not realistic, approximation of competition, succession, and other variable factors of a food web.

© Annenberg Foundation 2014. All rights reserved. Legal Policy